How big a blow will Ali Larijani’s killing prove to be for Iran?

Tehran is confronting a renewed leadership crisis after Israel confirmed the assassination of Ali Larijani, Iran’s secretary of the Supreme National Security Council, on March 17 in an air strike on the eastern outskirts of Tehran.

Described by Israel as Iran’s “de facto leader”, Larijani is the most senior figure eliminated since Supreme Leader Ali Khamenei’s killing on February 28, the first day of the US-Israeli war against Iran.

Larijani, 67, filled the power vacuum left by Khamenei’s death, emerging as the country’s “most important figure” during the two and a half weeks of war.

A scion of an elite political and clerical family, he served three consecutive terms as speaker of parliament (2008-2020), led the state broadcaster for 11 years, acted as chief nuclear negotiator with Western powers, and brokered Iran’s landmark 25-year strategic partnership with China.

A profile in Israeli newspaper Haaretz described him as the “flesh and blood” of the Iranian ruling setup.

Experts say Iran is undergoing a strategic and operational disruption in the aftermath of Larijani’s killing, with the high-profile assassination likely to accelerate Tehran’s shift towards uncompromising resistance.

Gokhan Ereli, an independent researcher and Middle East expert, tells TRT World that Larijani was one of Iran’s “primary crisis managers”.

“He was one of the most vital links between Iran’s military, clerical and diplomatic spheres,” he says.

Larijani’s removal amounts to a “functional decapitation strategy” by Israel and the US.

“It is too disruptive for the Iranian state and society,” he says.

A former Revolutionary Guard (IRGC) commander, Larijani obtained his PhD on the philosophy of mathematics of 18th-century German intellectual Immanuel Kant. Three of the six books he wrote in the years that followed were about the German philosopher.

Larijani combined ideological loyalty with technocratic pragmatism. Western governments held him responsible for Iran’s recent domestic crackdown on protesters that reportedly left thousands of people dead.

Despite his deep connections with the clerical establishment over the decades, he was disqualified in 2021 and 2024 from running for president owing to his “insufficiently devout lifestyle”. 

After Khamenei’s killing, he became the public face of defiance, while coordinating responses across military and political segments of the Iranian government.

Ereli says Larijani held a “unique ability to translate” the IRGC’s military objectives into political and diplomatic strategies. His killing will slow down Iran’s decision-making cycle in the immediate term, he says. 

“The absence of Larijani will embolden those who favour total resistance,” Ereli adds.

“The hardening of the Iranian government’s resolve is the most likely outcome.”

Iranian army chief Amir Hatami has vowed a “decisive” response. In its first act of retaliation after the killing of Larijani, Tehran fired missiles at Israel on Wednesday, killing at least two people near Tel Aviv.

Iranian President Masoud Pezeshkian has reportedly given the armed forces “broad authority” to act independently if more senior leaders are incapacitated in the same manner.

Funerals for Larijani and others are scheduled for Wednesday amid heightened anxiety in Tehran.

Omair Anas, assistant professor of international relations at Ankara Yildirim Beyazit University, tells TRT World that the killing of Larijani is the “biggest setback” to the Iranian government.

Larijani was “the main firefighter at the helm of this crisis”, who enjoyed decades of trust from the slain supreme leader.

“With him gone, the decision-making and strategic thinking of the Iranian government will face temporary disruption and mismatch,” Anas says.

“It is not a good sign at all for the government’s survival,” he adds.

Military in the driving seat

Experts foresee accelerated dominance of the IRGC, the most powerful branch of the Iranian armed forces that directly answers to the supreme leader, in how Iran fights the war going forward.

Ereli says that Larijani’s influence was “personal rather than purely institutional”. He was a “bridge figure” between the top clergy, holding firm control over the levers of power and IRGC officials in Tehran.

The IRGC has increasingly sidelined civilian politicians, Ereli says. 

Without Larijani acting as a buffer, the military-security apparatus is “highly likely” to absorb his formal powers.

This leaves Mojtaba Khamenei — the new supreme leader and son of the slain Ali Khamenei – “more dependent” on the IRGC sphere, potentially making the new leader a “hostage to military interests”.

Anas says that replacements of Larijani exist, including hardliner Saeed Jalili. But he adds that there are “more vacancies than available candidates” for many top positions.

Most senior figures are already on Israel’s hit list, forcing Iran to shift towards “undeclared assignments” to avoid further assassinations.

Larijani’s death may have an effect on informal diplomatic channels he personally nurtured, particularly with Oman and Russia, Ereli says.

But he cautions against over-personalising state relations, saying that ties with Oman, Russia and China are “embedded in the state” and will “probably continue, though potentially with less flexibility and more security-sector control”.

As for the question of escalation versus de-escalation in the aftermath of high-value assassinations, experts reject the notion that Iran may tone down its rhetoric or scale back military resistance.

In fact, Ereli holds that Larijani viewed “calibrated regional escalation” – such as support for strikes on US bases in the Middle East – as one tool among many, not a substitute for diplomacy.

But post-Larijani, Iran is likely to narrow its focus to “purely military responses”.

The prospect of a limited ceasefire or a grand bargain has become a lower-probability outcome, he adds.

“Diplomacy may be abandoned for a while,” Ereli says.

According to Anas, Larijani possessed diplomatic skills to outsmart Israelis, find a middle ground, and reach an agreement.

Israel eliminated Larijani not because he was dangerous, but because he could lead Iran to a diplomatic solution – something that (Prime Minister Benjamin) “Netanyahu dislikes the most”.

“Israelis are primarily pushing Iran to a civil war and chaos by eliminating everyone who can make a deal,” he says.